package chouXiangLeiHeJieKou.ChouXiangLeiHeJieKou2.demo3;

abstract class A implements USB{

}

public class Test {
    public static void main(String[] args) {
        Computer computer=new Computer();
        computer.open();

        computer.useUsbDevice(new KeyBoard());
        computer.useUsbDevice(new Mouse());

        computer.close();
    }
}
